The present invention relates in general to the generation of plasma in a gas, and more specifically to plasma generating devices with inbuilt inductance. Plasma generation is used in particular for the controlled ignition of internal combustion engines by the electrodes of a spark plug, but can also be used, for example, for sterilization in an air-conditioning method or pollution reduction systems.
More specifically, the invention relates to a plasma generating device comprising two electrodes, a series resonator with a resonant frequency higher than 1 MHz and comprising a capacitor equipped with two terminals and an inductive coil surrounded by a shield, the capacitor and the coil being arranged in series, the electrodes being connected to the respective terminals of the capacitor.
A device such as this is described in particular in the form of a spark plug in document FR 2 859 830. This type of spark plug exhibits low internal parasitic capacitances and forms a series resonator that has a high Q-factor. Although this device is able to sustain a radiofrequency voltage between its electrodes to generate a plasma, optimizing it has hitherto remained problematic.